The present invention pertains generally to the fusion of plastic pipe and specifically to the external cleaning of the pipe prior to fusion.
Polyethylene pipe is used commercially for the construction of pipelines for various applications such as natural gas, water, sewer, and other materials. In addition, polyethylene pipe may be used as conduit to protect transmission cables such as high voltage electricity, fiber optic telecommunication, telephone, cable television, and other signal cables.
Polyethylene pipe is typically joined through a process called fusion welding, the most common joint being a butt joint. A butt joint is formed by holding the two sections of pipe rigidly, performing a facing operation to square the ends of the pipes and prepare the pipes for welding, then heating the prepared faces of the pipes on a hot plate to the melting point, removing the heating element, and forcing the two melted faces together. The resulting joint may be cooled before being subjected to any handling forces. The result is a fused joint that is as strong or stronger than the parent material and is very reliable.
U.S. Pat. No. 4,990,209 issued to George Rakes entitled “Self Propelled Fusion Machine” (Rakes) is a machine adapted to perform butt joints on polyethylene pipe as described above. Rakes is incorporated herein by reference for all that it discloses and teaches. The Rakes machine performs the sequence of butt fusing in a semi automated fashion, with provisions for easily loading and unloading the pipe as it is welded. Additionally, the Rakes device performs the butt fusion process in an enclosed environment, adding to the consistency and speed to a pipeline construction.
When machines such as the Rakes device are used in the field, often rain, snow, mud and other debris may be present on the outside of the pipe. As the sections of pipe are handled and loaded into the machine for fusion, the debris should be removed, causing extra time to be taken to clean the pipes beforehand or to clean the equipment afterwards.
It would therefore be advantageous to provide a device and method of cleaning pipe sections prior to welding. It would be further advantageous if the method did not require any extra work on the part of any workers constructing a pipeline.